A study of surfaces and near surface composition of a sample is accomplished with a well collimated ion or electron beam to impinge the sample and an efficient analyzer for the secondary radiations scattered or evolved from the surface. A well-known form of such apparatus is the cylindrical mirror analyzer (CMA) with internal axially aligned electron source. A representative example of such prior art apparatus is the Varian Model 981-2707 cylindrical mirror analyzer and integral gun, Model 981-2773. This apparatus comprises coaxial cylinders with an electron gun disposed along the common axis and surrounded by the inner cylindrical wall of the analyzer.
It has been known previously to employ multiple stages of cylindrical analyzers and the theoretical analyses of the optics thereof is well understood.